@misc{indiciae65c3317f8dc4,
  title = {Coal resources of the Trinidad coal field in Huerfano and Las Animas counties, Colorado},
  author = {Ross Byron Johnson},
  year = {1961},
  doi = {10.3133/b1112e},
  url = {https://pubs.usgs.gov/publication/b1112E},
  note = {Source identifier: b1112E}
}